Enterococci are frequently causes of serious infections in newborns and severely immunocompromised patients. Until recently, infections have been adequately controlled using antibiotics. However, drug-resistant bacterial strains are emerging, and infection by strains resistant to all presently available antibiotics may become a serious problem in the near future. It is therefore essential that new methods for controlling enterococcal infections be developed.
The present invention describes a procedure for purifying polysaccharides from the cell membranes of E. faecalis. When administered to an appropriate host, these antigens induce the production of high titers of opsonic antibodies that kill both E. faecalis and E. faecium.